Photoresists and methods for use thereof

ABSTRACT

New photoresists are provided that comprise preferably as distinct components: a resin, a photoactive component and a phenolic component Preferred photoresists of the invention are can be useful for ion implant lithography protocols.

This application claims the benefit of priority under 35 U.S.C. §119(e)to U.S. Provisional Application No. 61/286,756, filed Dec. 15, 2009, theentire contents of which application are incorporated herein byreference.

The invention relates to new photoresists that comprising a phenoliccomponent and that are particularly useful for ion implant lithographyapplications. Photoresists of the invention can exhibit enhanced depthof focus (exposure latitude).

Photoresists are photosensitive films used for transfer of images to asubstrate. A coating layer of a photoresist is formed on a substrate andthe photoresist layer is then exposed through a photomask to a source ofactivating radiation.

Ion implantation techniques have been employed for doping semiconductorwafers. By this approach, an ion beam implanter generates an ion beamwithin an evacuated (low pressure) chamber, and the ions are directedand “implanted” to the wafer.

Significant problems arise however with current ion implantationmethods. On particular, acceptable depth of focus (DOF) can be difficultto obtain, particularly in high resolution applications and where denseand isolated features are being imaged together. A developed resist lineor other feature is generally considered “isolated” if it is spaced fromthe closest adjacent resist feature a distance equal to two or moretimes the line width. Thus, e.g., if a line is printed at a 0.25 μmwidth, that line would be considered isolated (rather than dense) if thenext adjacent resist feature was spaced at least about 0.50 microns fromthe line.

It would be desirable to have new photoresist systems that would providegood resolution, including good depth of focus.

We now provide new chemically-amplified photoresist compositions forshort wavelength imaging (e.g. 193 nm) that comprise a phenoliccomponent in addition to a resin that contains photoacid-labile groups,and one or more photoacid generator compounds. It has been surprisinglyfound that addition of a phenolic component (such as a phenolic resin)can significantly enhance the depth of focus (exposure latitude) of aphotoresist. Photoresists of the invention are particularly useful inion implantation lithography protocols.

The phenolic component is suitably phenolic resin, e.g.polyhydroxystyrene, that can be present in relatively minor amounts e.g.less than 10, 8, 6, 5, 4, or 2 or even 1 weight percent of total solids(all components except solvent carrier) of a photoresist composition. Inaddition to polymeric phenolic compounds, non-polymeric materials thatcomprise one or more phenolic groups also may be employed.

Preferred resists of the invention can be imaged at short wavelengths,including sub-300 nm and sub-200 nm such 248 nm, 193 nm and EUV.

Particularly preferred photoresists of the invention contain an phenoliccomponent as disclosed herein, an imaging-effective amount of one ormore photoacid generator compounds (PAGs) and a resin that is selectedfrom the group of:

1) a phenolic resin that contains acid-labile groups that can provide achemically amplified positive resist particularly suitable for imagingat 248 nm. Particularly preferred resins of this class include: i)polymers that contain polymerized units of a vinyl phenol and an alkylacrylate, where the polymerized alkyl acrylate units can undergo adeblocking reaction in the presence of photoacid. Exemplary alkylacrylates that can undergo a photoacid-induced deblocking reactioninclude e.g. t-butyl acrylate, t-butyl methacrylate, methyladamantylacrylate, methyl adamantyl methacrylate, and other non-cyclic alkyl andalicyclic acrylates that can undergo a photoacid-induced reaction, suchas polymers in U.S. Pat. Nos. 6,042,997 and 5,492,793, incorporatedherein by reference; ii) polymers that contain polymerized units of avinyl phenol, an optionally substituted vinyl phenyl (e.g. styrene) thatdoes not contain a hydroxy or carboxy ring substituent, and an alkylacrylate such as those deblocking groups described with polymers i)above, such as polymers described in U.S. Pat. No. 6,042,997,incorporated herein by reference; and iii) polymers that contain repeatunits that comprise an acetal or ketal moiety that will react withphotoacid, and optionally aromatic repeat units such as phenyl orphenolic groups.

2) a resin that is substantially or completely free of phenyl or otheraromatic groups that can provide a chemically amplified positive resistparticularly suitable for imaging at sub-200 nm wavelengths such as 193nm. Particularly preferred resins of this class include: i) polymersthat contain polymerized units of a non-aromatic cyclic olefin(endocyclic double bond) such as an optionally substituted norbornene,such as polymers described in U.S. Pat. No. 5,843,624 incorporatedherein by reference; ii) polymers that contain alkyl acrylate units suchas e.g. t-butyl acrylate, t-butyl methacrylate, methyladamantylacrylate, methyl adamantyl methacrylate, and other non-cyclic alkyl andalicyclic acrylates; such polymers have been described in U.S. Pat. No.6,057,083.

Resists of the invention also may comprise a mixture of distinct PAGs,typically a mixture of 2 or 3 different PAGs, more typically a mixturethat consists of a total of 2 distinct PAGs.

The invention also provide methods for forming relief images of thephotoresists of the invention, including methods for forming highlyresolved patterned photoresist images (e.g. a patterned line havingessentially vertical sidewalls) of sub-quarter micron dimensions orless, such as sub-0.2 or sub-0.1 micron dimensions.

The invention further comprises articles of manufacture comprisingsubstrates such as a microelectronic wafer having coated thereon thephotoresists and relief images of the invention. The invention alsoincludes methods to manufacture microelectronic wafers and otherarticles.

Additionally, as discussed, in a preferred aspect, the inventionprovided informed ion implantation processing. Such a process mayinclude implanting dopant ions (e.g. Group III and/or V ions such asboron, arsenic, phosphorus and the like) into a surface of a substrate(e.g. semiconductor wafer) having thereon an organic photoresist asdisclosed which serves as a mask. The resist-masked substrate may beplaced in a reaction chamber which can provide reduced pressure and aplasma of ions from an ionizable source. Those ions include dopants asmentioned which are electrically active when implanted into thesubstrate. Voltages may be applied in the reaction chamber (such asthrough electrically conductive chamber walls) to selectively implantthe dopant ions.

Other aspects of the invention are disclosed infra.

As discussed above, we now provide new photoresists that suitablycomprise a 1) a resin component which suitably may comprisephotoacid-labile groups, 2) one or more photoacid generator compoundsand 3) a phenolic component which may be polymeric or non-polymeric.Preferably, those components 1), 2) and 3) are distinct, i.e. notcovalently linked and are each different materials. Preferredphotoresists of the invention are positive-acting resists, particularlychemically-amplified resists. The invention also includesnegative-acting photoresists where the resist may comprise a resin, acrosslinking function and an phenolic component as disclosed herein.

Particularly photoresists of the invention will comprise as distinctcomponents a 1) a resin component, 2) one or more photoacid generatorcompounds and 3) a phenolic component which may be polymeric ornon-polymeric, where the resin component 1) does not comprise or is atleast essentially free (less than 5 weight percent) phenyl or phenolicgroups and preferably 50 percent of total repeat units of the resin arenon-aromatic, more preferably less than 40, or 35 total repeat units ofthe resin 1) are non-aromatic. In many preferred embodiments, resin 1)may be substantially free of any aromatic repeat units where less than15, 10, 5, 3, 2 or 1 percent of total repeat units of the resin arearomatic.

Particularly preferred phenolic components include phenolic resins whichmay be a homopolymer that comprises repeat units of a phenolic group(e.g. a poly(hydroxystyrene homopolymer) or may be a copolymer thatcomprises phenolic repeat units with other polymerized groups.

A phenolic component of a resist of the invention also may comprise avariety of other groups such as e.g. halogen, cyano, alkoxy, ether,optionally substituted C₁₋₂₀alkyl.

As discussed above, the phenolic component may be non-polymeric, i.e.not contain multiple repeat units. In many preferred aspects however,the phenolic component is polymeric. In such aspects of the invention,the phenolic component additive suitably may have relatively highermolecular weights, e.g. a molecular weight in excess of 1,000, 2,000,5,000, 10,000, 15,000, 20,000 weight average molecular weight.

Preferably, the phenolic component will be stable in a photoresistcomposition and not interfere with lithographic processing of theresist. That is, the phenolic component preferably does not promotepremature degradation of a resist (i.e. reduced shelf life) ornecessitate alternate lithographic processing conditions.

The phenolic component typically will be a further, distinct resistcomponent beyond other resist components of e.g. an photoacid-labile ordeblocking resin, photoacid generator, basic additive,surfactant/leveler, plasticizer, and/or solvent. Thus, in at leastcertain aspects, preferred phenolic component for use in a resist willnot contain photoacid-labile moieties such as a photoacid-labile esteror acetal groups that undergo a deblocking reaction as a consequence ofa photoresist exposure step.

However, the phenolic component may provide other function to a resistcomposition, such as provide or enhance solvency of solid components.However, unlike other volatile solvents, a phenolic component additivewill remain in a resist layer in effective amounts after anypre-exposure thermal treatment, e.g. preferably at least about 10, 20,30, 40, or 50 mole percent of the amount of the phenolic componentformulated in the liquid resist composition will remain in the resistcomposition after any pre-exposure thermal treatment. Typically, only asmall amount of the phenolic component additive need remain in a resistcoating layer after any thermal treatments to achieve effective results,e.g. the phenolic component additive may be suitably present in anamount of from about 0.05 or 0.1 weight percent to about 5 weightpercent of total material of the resist layer after volatile solventremoval.

As stated herein, various substituent groups of components of resist maybe optionally substituted. Substituted moieties are suitably substitutedat one or more available positions by, e.g., halogen such as F, Cl Brand/or I, nitro, cyano, sulfono, alkyl including C₁₋₁₆ alkyl with C₁₋₈alkyl being preferred, haloalkyl such as fluoroalkyl (e.g.trifluoromethyl) and perhaloalkyl such as perfluoroC₁₋₄alkyl, alkoxyincluding C₁₋₁₆ alkoxy having one or more oxygen linkages with C₁₋₈alkoxy being preferred, alkenyl including C₂₋₁₂ alkenyl with C₂₋₈alkenyl being preferred, alkenyl including C₂₋₁₂ alkenyl with C₂₋₈alkynyl being preferred, aryl such as phenyl or naphthyl and substitutedaryl such as halo, alkoxy, alkenyl, alkynyl and/or alkyl substitutedaryl, preferably having the number of carbon atoms mentioned above forcorresponding groups. Preferred substituted aryl groups includesubstituted phenyl, anthracenyl and naphthyl.

The photoresists of the invention typically comprise a resin binder anda photoactive component and a phenolic component. In many embodiments,preferred are chemically amplified positive-acting resists. A number ofsuch resist compositions have been described, e.g., in U.S. Pat. Nos.4,968,581; 4,883,740; 4,810,613 and 4,491,628 and Canadian PatentApplication 2,001,384.

Photoresists for use in the invention also comprise a photoactivecomponent particularly one or more photoacid generators (i.e. “PAGs”)that is suitably employed in an amount sufficient to generate a latentimage in a coating layer of the resist upon exposure to activatingradiation. Preferred PAGs for imaging at 193 nm and 248 nm imaginginclude imidosulfonates such as compounds of the following formula:

wherein R is camphor, adamantane, alkyl (e.g. C₁₋₁₂ alkyl) andfluoroalkyl such as fluoro(C₁₋₁₈alkyl) e.g. RCF₂— where R is optionallysubstituted adamantyl.

Other known PAGS also may be employed in the resists of the invention.Particularly for 193 nm imaging, generally preferred are PAGS that donot contain aromatic groups, such as the above-mentionedimidosulfonates, in order to provide enhanced transparency.

Other suitable photoacid generators for use in present photoresistsinclude for example: onium salts, for example, triphenylsulfoniumtrifluoromethanesulfonate, (p-tert-butoxyphenyl)diphenylsulfoniumtrifluoromethanesulfonate, tris(p-tert-butoxyphenyl)sulfoniumtrifluoromethanesulfonate, triphenylsulfonium p-toluenesulfonate;nitrobenzyl derivatives, for example, 2-nitrobenzyl p-toluenesulfonate,2,6-dinitrobenzyl p-toluenesulfonate, and 2,4-dinitrobenzylp-toluenesulfonate; sulfonic acid esters, for example,1,2,3-tris(methanesulfonyloxy)benzene, 1,2,3-tris(trifluoromethanesulfonyloxy)benzene, and1,2,3-tris(p-toluenesulfonyloxy)benzene; diazomethane derivatives, forexample, bis(benzenesulfonyl)diazomethane,bis(p-toluenesulfonyl)diazomethane; glyoxime derivatives, for example,bis-O-(p-toluenesulfonyl)-α-dimethylglyoxime, andbis-O-(n-butanesulfonyl)-α-dimethylglyoxime; sulfonic acid esterderivatives of an N-hydroxyamide compound, for example,N-hydroxysuccinimide methanesulfonic acid ester, N-hydroxysuccinimidetrifluoromethanesulfonic acid ester; and halogen-containing triazinecompounds, for example,2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, and2-(4-methoxynaphthyl)-4,6-bis(trichloromethyl)-1,3,5-triazine. One ormore of such PAGs can be used.

A preferred optional additive of photoresist used in accordance with theinvention is an added base, particularly tetramethylammonium hydroxide(TBAH), or tetramethylammonium lactate, which can enhance resolution ofa developed resist relief image. For resists imaged at 193 nm, apreferred added base is a lactate salt of tetramethylammonium hydroxideas well as various other amines such as triisopropanol, diazabicycloundecene or diazabicyclononene. The added base is suitably used inrelatively small amounts, e.g. about 0.03 to 5 percent by weightrelative to the total solids.

Photoresists used in accordance with the invention also may containother optional materials. For example, other optional additives includeanti-striation agents, plasticizers, speed enhancers, etc. Such optionaladditives typically will be present in minor concentrations in aphotoresist composition except for fillers and dyes which may be presentin relatively large concentrations, e.g., in amounts of from about 5 to30 percent by weight of the total weight of a resist's dry components.

The photoresists used in accordance with the invention are generallyprepared following known procedures. For example, a resist of theinvention can be prepared as a coating composition by dissolving thecomponents of the photoresist in a suitable solvent such as, e.g., aglycol ether such as 2-methoxyethyl ether (diglyme), ethylene glycolmonomethyl ether, propylene glycol monomethyl ether; propylene glycolmonomethyl ether acetate; lactates such as ethyl lactate or methyllactate, with ethyl lactate being preferred; propionates, particularlymethyl propionate, ethyl propionate and ethyl ethoxy propionate; aCellosolve ester such as methyl Cellosolve acetate; an aromatichydrocarbon such toluene or xylene; or a ketone such as methylethylketone, cyclohexanone and 2-heptanone. Typically the solids content ofthe photoresist varies between 5 and 35 percent by weight of the totalweight of the photoresist composition. Blends of such solvents also aresuitable.

Liquid photoresist compositions may be applied to a substrate such as byspinning, dipping, roller coating or other conventional coatingtechnique. When spin coating, the solids content of the coating solutioncan be adjusted to provide a desired film thickness based upon thespecific spinning equipment utilized, the viscosity of the solution, thespeed of the spinner and the amount of time allowed for spinning.

Photoresist compositions used in accordance with the invention aresuitably applied to substrates conventionally used in processesinvolving coating with photoresists. For example, the composition may beapplied over silicon wafers or silicon wafers coated with silicondioxide for the production of microprocessors and other integratedcircuit components. Aluminum-aluminum oxide, gallium arsenide, ceramic,quartz, copper, glass substrates and the like are also suitablyemployed. Photoresists also may be suitably applied over anantireflective layer, particularly an organic antireflective layer.

Following coating of the photoresist onto a surface, it may be dried byheating to remove the solvent until preferably the photoresist coatingis tack free.

The photoresist layer is then exposed to imaging radiation. An immersionlithography process may be employed. References herein to “immersionexposing” or other similar term indicates that exposure is conductedwith such a fluid layer (e.g. water or water with additives) interposedbetween an exposure tool and the coated photoresist composition layer.

The photoresist composition layer is suitably patterned exposed toactivating radiation with the exposure energy typically ranging fromabout 1 to 100 mJ/cm², dependent upon the exposure tool and thecomponents of the photoresist composition. References herein to exposinga photoresist composition to radiation that is activating for thephotoresist indicates that the radiation is capable of forming a latentimage in the photoresist such as by causing a reaction of thephotoactive component (e.g. producing photoacid from the photoacidgenerator compound).

As discussed above, photoresist compositions are preferablyphotoactivated by a short exposure wavelength, particularly a sub-400nm, sub-300 and sub-200 nm exposure wavelength, with I-line (365 nm),248 nm and 193 nm being particularly preferred exposure wavelengths aswell as EUV.

Following exposure, the film layer of the composition is preferablybaked at temperatures ranging from about 70° C. to about 160° C.Thereafter, the film is developed, preferably by treatment with anaqueous based developer such as quaternary ammonium hydroxide solutionssuch as a tetra-alkyl ammonium hydroxide solution; various aminesolutions preferably a 0.26 N tetramethylammonium hydroxide, such asethyl amine, n-propyl amine, diethyl amine, di-n-propyl amine, triethylamine, or methyldiethyl amine; alcohol amines such as diethanol amine ortriethanol amine; cyclic amines such as pyrrole, pyridine, etc.

Photoresist and methods of the invention can be employed in a wide rangeof application, including e.g. in the manufacture of thin film heads(e.g. 3 to 5 μm), magnetic disks, CD masks, and back-end implants.

Also, photoresists of the invention can be useful to form metal bumps ona semiconductor wafer. Such processing can include: a) disposing on asemiconductor wafer a photoresist of the invention, preferably toprovide a thick film coating layer such as a dried resist coating layerof 50 μm or greater; c) imagewise exposing the layer of photosensitivecomposition to actinic radiation, including sub-300 or sub-200 nmradiation particularly 248 nm and 193 nm ; d) developing the exposedlayer of photosensitive composition to provide patterned areas; e)depositing a metal into the patterned areas; and f) removing the exposedphotosensitive composition to provide a semiconductor wafer having metalbumps.

In such bump-forming methods, the photoresist layer is imaged so as toform apertures such as vias in the photosensitive layer. In suchprocess, the photosensitive layer is disposed on a conductive layer onthe electronic device. Exposure of the photosensitive composition andsubsequent development provides defined holes (vias) in thephotosensitive composition and exposes the underlying conductive layer.Accordingly, the next step of the process is to deposit metal or metalalloy bumps with the defined holes (vias). Such metal deposition may beby electroless or electrolytic deposition processes. Electrolytic metaldeposition is preferred. In an electrolytic metal deposition process,the electronic device substrate, i.e. semiconductor wafer, functions asthe cathode.

Prior to deposition of a metal or metal alloy, such as that suitable asa solder, a conductive layer such as copper or nickel may be depositedby sputtering, electroless deposition and the like, to form theunder-bump-metal. Such under-bump-metal layer is typically from 1000 to50,000 Å in thickness and acts as a wettable foundation to thesubsequently plated solder bump.

A wide variety of metals may be deposited electrolessly, including, butnot limited to, copper, tin-lead, nickel, gold, silver, palladium, andthe like. Suitable metals and metal alloys that may be depositedelectrolytically include, but are not limited to, copper, tin, tin-lead,nickel, gold, silver, tin-antimony, tin-copper, tin-bismuth, tin-indium,tin-silver, palladium, and the like. Such metal plating baths are wellknown to those skilled in the art and are readily available from avariety of sources, such as Rohm and Haas.

In one embodiment, the metal deposits on the semiconductor wafer areuseful as solder bumps. Accordingly, it is preferred that the metalbumps are solderable metals and metal alloys, such as tin, tin-lead,tin-copper, tin-silver, tin-bismuth, tin-copper-bismuth,tin-copper-silver, and the like. Suitable metals and metal alloys forsolder bump formation are disclosed in U.S. Pat. Nos. 5,186,383;5,902,472; 5,990,564; 6,099,713; and 6,013,572, as well as EuropeanPatent Application No. EP 1 148 548 (Cheung et al.), all of which arehereby incorporated by reference. Exemplary metals and metal alloysinclude, but are not limited to: tin; tin-copper alloy having less than2% wt copper and preferably about 0.7% wt copper; a tin-silver alloyhaving less than 20% wt silver and preferably from 3.5 to 10% wt silver;a tin bismuth alloy having from 5 to 25% wt bismuth and preferably about20% wt bismuth; and a tin-silver-copper alloy having less than 5% wtsilver and preferably about 3.5% wt silver, less than 2% wt copper andpreferably about 0.7% wt copper, and the balance being tin. In oneembodiment, the metal alloys used for solder bumps are lead-free, i.e.they contain ≦10 ppm of lead.

In general, suitable electrolytic metal plating baths are acidic andcontain acid, water a soluble form of the metal or metals to bedeposited and optionally one or more organic additives, such asbrighteners (accelerators), carriers (suppressors), levelers, ductilityenhancers, wetting agents, bath stabilizers (particularly fortin-containing baths), grain refiners and the like. The presence, typeand amount of each optional component varies depending upon theparticular metal plating bath used. Such metal plating baths aregenerally commercially available, such as from Shipley Company.

In such a process, the resist composition functions as a protectivelayer to areas that are not to be plated. Following metal deposition,the remaining resist composition is stripped, such as by using acommercially available N-methylpyrrolidone (“NMP”) based stripper at atemperature of about 40° to 69° C. Suitable strippers are available froma variety of sources, such as Shipley-SVC, Sunnyvale, Calif.

All documents mentioned herein are incorporated herein by reference. Thefollowing non-limiting example is illustrative of the invention.

EXAMPLE 1 Resist Preparation

A photoresist is prepared by admixing the following components (1through 5 below) where amounts are expressed as weight percent of totalweight of the resist.

1. Resin. The resin of the photoresist is terpolymer of(2-methyl-2-adamantyl methacrylate/beta-hydroxy-gamma-butyrolactonemethacrylate/cyano-norbornyl methacrylate present in 10.80 weightpercent based on total weight of the fluid photoresist.

2. Photoacid generator compound (PAG). The PAG is t-butyl phenyltetramethylene sulfonium perfluorobutanesulfonate present in 2.5 weightpercent of the total weight of the fluid photoresist.

3. Basic additive. The basic additive is N-Alkyl Caprolactam in anamount of 0.017 weight % based on total weight of the photoresistcomposition.

4. Phenolic component. The pnheolic component is poly(hydroxystyrene)resin (weight average molecular weight about 10,000) present in anamount of 3.5 weight present based on total weight of the photoresist.

5. Solvent. The solvent is ethyl lactate to provide balance of resist.

EXAMPLE 2 Lithographic Processing

The formulated resist composition of Example 1 is spin coated onto aSiON wafer surface and softbaked via a vacuum hotplate at 90° C. for 60seconds. The resist coating layer is exposed through a photomask at 193nm, and then the exposed coating layers are post-exposure baked at 110°C. The coated wafers are then treated with 0.26N aqueoustetrabutylammonium hydroxide solution to develop the imaged resistlayer.

After formation of the photoresist relief image, the substrate (withresist mask) is exposed to high energy (>20 eV, reduced pressureenvironment) phosphorus-ion implant processing.

What is claimed is:
 1. A method for providing an ion-implantedsemiconductor substrate comprising: providing a semiconductor substratehaving coated thereon a relief image of chemically-amplifiedpositive-acting photoresist composition, wherein the photoresistcomprises as distinct components (1) a resin wherein less than 15percent of total repeat units of the resin are aromatic, (2) aphotoactive component and (3) a phenolic component; and applying ions tothe substrate.
 2. The method of claim 1 wherein the phenolic componentis a phenolic resin.
 3. The method of claim 1 wherein the photoresist isa chemically amplified positive photoresist and the resin componentcomprises a resin that comprises less than 50 weight percent aromaticgroups.
 4. A method for forming a photoresist relief image comprising:(a) applying on a substrate a photoresist comprising as distinctcomponents (1) a resin wherein less than 15 percent of total repeatunits of the resin are aromatic, (2) a photoactive component and (3) aphenolic component; and (b) exposing the photoresist coating layer topatterned activating radiation.
 5. The method of claim 1 wherein thephotoresist composition is applied on an inorganic surface.
 6. Themethod of claim 1 wherein the phenolic component is a resin.
 7. Themethod of claim 1 wherein the phenolic component is a polyhydroxystyreneresin.
 8. The method of claim 1 wherein the resin comprisesphotoacid-labile groups.
 9. The method of claim 1 wherein the phenoliccomponent does not contain photoacid-labile moieties.
 10. The method ofclaim 4 wherein the photoresist is exposed with sub-200 nm wavelengthradiation.
 11. The method of claim 4 wherein the phenolic component is aresin.
 12. The method of claim 4 wherein the phenolic component is apolyhydroxystyrene resin.
 13. The method of claim 4 wherein the phenoliccomponent does not contain photoacid-labile moieties.
 14. A method forforming a photoresist relief image comprising: (a) applying on asubstrate a photoresist comprising as distinct components (1) a resin,(2) a photoactive component and (3) a phenolic component that does notcontain photoacid-labile moieties; and (b) exposing the photoresistcoating layer to patterned activating radiation.
 15. A method forforming a photoresist relief image comprising: (a) applying on asubstrate a photoresist comprising as distinct components (1) a resin,(2) a photoactive component and (3) a phenolic component; and (b)exposing the photoresist coating layer to patterned sub-200 nmactivating radiation.